## Arithmetic and Geometric Sequences and Series Solver

A program that will identify and then solve Arithmetic and Geometric Sequences and Series

after the user inputs the first three terms, a desired unknown term to be calculated,

and a starting and ending term for finding the sum of the related series.

The Arithmetic Sequence and Series Formulas used are:

- a
_{n} = a_{1} + (n -1)*d where d = common difference
- S
_{n} = (n/2)(a_{1} + a_{n})

The Geometric Sequence and Series Formulas used are:

- a
_{n} = a_{1} * r^{n-1} where r = common ratio
- S
_{n} = a_{1} * (1-r^{n})/(1-r)
- S
_{∞} = a_{1} * (1)/(1-r), where -1<r<1

This program is written in JavaScript.

By Mr. C. July 18, 2015